Initiators for living carbocationic polymerization

ABSTRACT

In various embodiments, the present invention is directed to new low cost initiator compositions for use with the production of well-defined telechelic PIBs (by LC + P of isobutylene). In various other embodiments, the present invention is directed to methods for using these novel compositions as initiators for isobutylene (IB) and other cationically polymerizable monomers, such as styrene and its derivatives. In still other embodiments, the present invention is directed to structurally new, allyl (and chlorine) telechelic PIBs formed from these new initiator compositions and their derivatives (in particular, hydroxyl telechelic PIB and amine telechelic PIB). In yet other embodiments, the present invention is directed to structurally new polyurethanes, polyureas, and polyurethane ureas made using telechelic PIBs formed from these new initiator compositions.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a bypass continuation-in-part of InternationalPatent Application Serial No. PCT/US17/14280, filed Jan. 20, 2017, whichclaims the benefit of U.S. Provisional Patent Application Ser. No.62/404,418 entitled “Novel Initiators for Living CarbocationicPolymerization” filed Oct. 5, 2016, and also claims the benefit of U.S.Provisional Patent Application Ser. No. 62/281,243, also entitled “NovelInitiators for Living Carbocationic Polymerization,” filed Jan. 21,2016, and this application separately claims the benefit of U.S.Provisional Patent Application Ser. No. 62/530,889 entitled “Low CostBifunctional Initiators for Bidirectional Living Cationic Polymerizationof Olefins. I. Isobutylene,” filed Jul. 11, 2017, all said applicationsbeing incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

One or more embodiments of the present invention relates to a novelinitiator for living carbocationic polymerizations (LC⁺Ps). In certainembodiments, the present invention relates to novel monofunctional,difunctional and trifunctional LC⁺P initiators, methods for theirsynthesis, and polymers made therefrom.

BACKGROUND OF THE INVENTION

Carbocationic polymerizations in general and living carbocationicpolymerizations in particular are of great scientific and practicalimportance for the creation of useful materials. Living carbocationicpolymerizations (LC⁺Ps) proceed in the absence of chain transfer andtermination (collectively termed chain breaking) and lead towell-defined designed useful polymers. LC⁺Ps lead to predetermineddegrees of polymerization (molecular weights), narrow molecular weightdistributions, desirable end-groups, and sequential (block, graft, etc.)polymers. The mechanism of LC⁺Ps is well known in the art. (See,Designed Polymers by Carbocationic Macromolecular Engineering, by J. P.Kennedy and B. Ivan, Hanser pub, 1992, the disclosure of which isincorporated herein by reference in its entirety). The chemistry ofinitiation of cationic polymerizations is discussed in detail inCarbocationic Polymerization, by J. P. Kennedy and E Marechal, Wiley,1982, pp. 81-116, and specifically that of LC⁺P, pp 9-31, the disclosureof which is incorporated herein by reference in its entirety.

The initiator that is used world-wide for the production of well-definedtelechelic PIBs (by LC⁺P of isobutylene) by academic and industrialinvestigators, is 5-tert-butyl-1,3-bis(1-chloro-1-methylethyl)benzene(abbreviated herein as HDCCl, for hindered dicumyl chloride):

5-tert-butyl-1,3-bis (1-chloro-1-methylethyl)benzene (HDCCl) Otherinitiators commonly used for the synthesis of well-defined telechelicPIBs (by LC⁺P of isobutylene) include those described in U.S. Pat. No.5,733,998 to Kennedy et al. and U.S. Pat. No. 8,889,926 to Kennedy etal., the disclosure of which are incorporated herein by reference intheir entirety.

The synthesis of HDCCl occurs in several steps and requires the use ofan expensive starting material and costly reagents. (See, Wang, B.,Mishra, M. K., Kennedy J. P., Polymer Bulletin, 17, 205 (1987), thedisclosure of which is incorporated herein by reference in itsentirety.) HDCCl in conjunction with Friedel-Crafts acid co-initiators,e.g., TiCl₄, instantaneously initiates bi-directional LC⁺P ofisobutylene. The bulky tert butyl group in HDCCl is necessary as itprevents unacceptable intramolecular aromatic alkylation by the tertcation that arises by the first incorporated isobutylene molecule; inother words, in the absence of the tert butyl group in HDCClunacceptable facile zero order intramolecular aromatic alkylation by thefirst aliphatic tert cation would occur leading to an indanyl ring plusa proton as shown in Scheme 1 below.

If such intramolecular aromatic alkylation occurs, which is in fact achain transfer reaction, LC⁺P cannot take place because the expelledproton (see last formula in the above equation) would initiatepolymerization and would lead to polymers with useless “sterile” H— headgroup.

Accordingly, what is needed in the art is a low cost LC⁺P initiator thatin conjunction with one or more Friedel-Crafts acid co-initiators, suchas TiCl₄, initiates LC⁺P of isobutylene.

SUMMARY OF THE INVENTION

In various embodiments, the present invention is directed to new lowcost initiator compositions for use with the production of well-definedtelechelic PIBs (by LC⁺P of isobutylene). In various other embodiments,the present invention is directed to methods for using these novelcompositions as initiators for isobutylene (IB) and other cationicallypolymerizable co-monomers, such as styrene and its derivatives. In stillother embodiments, the present invention is directed to structurallynew, allyl (and chlorine) telechelic PIBs formed from these newinitiator compositions and their derivatives (in particular, hydroxyltelechelic PIB (HO—PIB—OH) for the production of new polyurethanes andamine telechelic PIB (H₂N—PIB—NH₂) for the production of polyrueas). Inyet other embodiments, the present invention is directed to structurallynew polyurethanes, polyureas, and polyurethane ureas made usingtelechelic PIBs formed from these new initiator compositions. In yetother embodiments, the present invention is directed to structurallycopolymers, such as styrene-isobutylene-styrene copolymers (SIBS).

In a first aspect, the present invention is directed to an initiatormolecule defined by one of the following formulas:

where each x is Cl, OH, or OCH₃. In one or more of these embodiments,the initiator molecule is a monofunctional, bifunctional ortrifunctional initiator.

In one or more embodiments, the initiator molecule of the presentinvention includes any one or more of the above referenced embodimentsof the first aspect of the present invention wherein the initiatormolecule is a monofunctional initiator having the formula:

wherein x is Cl, OH, or OCH₃.

In one or more embodiments, the initiator molecule of the presentinvention includes any one or more of the above referenced embodimentsof the first aspect of the present invention wherein the initiatormolecule is a bifunctional initiator having the formula:

wherein x is Cl, OH, or OCH₃.

In one or more embodiments, the initiator molecule of the presentinvention includes any one or more of the above referenced embodimentsof the first aspect of the present invention wherein the initiatormolecule is a trifunctional initiator having the formula:

wherein x is Cl, OH, or OCH₃.

In one or more embodiments, the initiator molecule of the presentinvention includes any one or more of the above referenced embodimentsof the first aspect of the present invention wherein the initiatormolecule is defined by the chemical formula2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene-4,9-diolor4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene.

In a second aspect, the present invention is directed to a telechelicpolyisobutylene composition comprising one, two, or threepolyisobutylene chains extending from the residue of an initiator asmolecule as claimed in claim 1. In some of these embodiments, each ofthe one, two, or three polyisobutylene chains further comprises aterminal functional group. In one or more of these embodiments, theterminal functional groups are selected from the group consisting ofallyl groups, hydroxyl groups, primary or tertiary alcohols, halides,amine groups, azide groups, thiol groups, furanyl groups, alkynylgroups, cyano groups, and combinations thereof.

In a third aspect, the present invention is directed to anallyl-telechelic polyisobutylene composition comprising a residue of theinitiator of claim 1. In one or more of these embodiments, theallyl-telechelic polyisobutylene composition comprises one, two or threeallyl-telechelic polyisobutylene chains extending from the initiatorresidue. In one or more of these embodiments the allyl-telechelicpolyisobutylene composition has the formula:

wherein each individual n is an integer from 2 to about 5,000.

In a fourth aspect, the present invention is directed to a primaryalcohol terminated polyisobutylene comprising a residue of the novelinitiator described above. In some of these embodiments, he primaryalcohol terminated polyisobutylene comprising one, two or three primaryalcohol terminated polyisobutylene chains extending from the initiatorresidue. In one or more embodiment, the primary alcohol terminatedpolyisobutylene has the formula:

wherein each individually n is an integer from 2 to 5,000.

In a fifth aspect, the present invention is directed to an amineterminated polyisobutylene comprising a residue of the novel initiatordescribed above. In some of these embodiments, the amine terminatedpolyisobutylene has the formula:

wherein each individual n is an integer from 2 to 5,000.

In a sixth aspect, the present invention is directed to apolyisobutylene-based polyurethane and/or polyurea comprising a residueof the initiator described above. In some of these embodiments, thepolyisobutylene-based polyurethane and/or polyurea has the formula:

where each n is an integer from 2 to 5,000, m is an integer from 2 to1,000,000, and R is a residue of toluene diisocyanate or 4,4′-diphenylmethane diisocyanate having the formula:

In some other of these embodiments, the polyisobutylene-basedpolyurethane and/or polyurea has the formula:

where each n is an integer from 2 to 5,000, m is an integer from 2 to1,000,000, and R is a residue of toluene diisocyanate or 4,4′-diphenylmethane diisocyanate having the formula:

In a seventh aspect, the present invention is directed to apolyisobutylene-based polyurethane comprising the reaction product of adiisocyanate and a primary alcohol terminated polyisobutylene comprisinga residue of the novel initiator described above. In some of theseembodiments, the primary alcohol terminated polyisobutylene furthercomprises one, two or three primary alcohol terminated polyisobutylenechains extending from the initiator residue. In one or more of theseembodiments, the primary alcohol terminated polyisobutylene has theformula:

wherein each individual n is an integer from 2 to 5,000.

In an eighth aspect, the present invention is directed to apolyisobutylene-based polyurea comprising the reaction product of adiisocyanate and an amine terminated polyisobutylene comprising aresidue of the initiator of claim 1. In some of these embodiments, theamine terminated polyisobutylene has the formula:

wherein each individual n is an integer from 2 to 5,000.

In a ninth aspect, the present invention is directed to apolystyrene-polyisobutylene-polystyrene co-polymer comprising a residueof the initiator described above.

In a tenth aspect, the present invention is directed to a method formmaking the novel initiator molecule described above comprising:dissolving 1,2,4,5-tetramethyl benzene or 1,2,3,5-tetramethyl benzene ina suitable solvent; combining an acetyl halide, aluminum chloride, and adry solvent in a suitable container and heating it to reflux for fromabout 6 to about 12 hours; adding the 1,2,4,5-tetramethyl benzene or1,2,3,5-tetramethyl benzene to the acetyl halide solution and stirringat reflux for an additional 10 to 14 hours; separating the resultingpolymer containing solution into organic and aqueous phases, washing theresulting organic phase with aqueous sodium carbonate, removing thesolvent, and drying the resulting product to produce the correspondingdiethanone; dissolving the corresponding diethanone in a suitablesolvent and irradiating it with ultraviolet light to form thecorresponding bis-benzocyclobutenol initiator molecule. In some of theseembodiments, the method further comprises the step of hydrochlorinatingthe bis-benzocyclobutenol initiator molecule to form the correspondingdichloro initiator molecule.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the features and advantages of thepresent invention, reference is now made to the detailed description ofthe invention along with the accompanying figures in which:

FIG. 1 is an H¹NMR spectrum of1,1′-(2,3,5,6-tetramethyl-1,4-phenylene)diethanone (diacetyl durene,DAD).

FIG. 2 is a schematic diagram of a photolysis apparatus for thesynthesis of2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene-4,9-diol(bBCB-ol).

FIG. 3 is a ¹H NMR spectrum of bBCB-ol.

FIG. 4 is a schematic diagram of a chlorination apparatus for use inchlorinating bBCB-ol to form4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene(bBdClCB)

FIG. 5 is a ¹H NMR spectrum of bBdClCB.

FIG. 6 is a ¹H NMR spectrum of allyl telechelic PIB made using a novellow cost initiator according to one or more embodiments of the presentinvention.

FIG. 7 is a GPC trace of allyl telechelic PIB synthesized with bBdClCB.

FIG. 8 is a ¹H NMR spectrum of allyl telechelic PIB synthesized withbBCB-ol.

FIG. 9 is a GPC trace of allyl telechelic PIB synthesized with bBCB-ol

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

In various embodiments, the present invention is directed to new lowcost initiator compositions for use with the production of well-definedtelechelic PIBs (by LC⁺P of isobutylene). In various other embodiments,the present invention is directed to methods for using these novelcompositions as initiators for isobutylene (IB) and other cationicallypolymerizable monomers, such as styrene and its derivatives. In stillother embodiments, the present invention is directed to structurallynew, allyl (and chlorine) telechelic PIBs formed from these newinitiator compositions and their derivatives (in particular HO—PIB—OHfor the production of new polyurethanes). In yet other embodiments, thepresent invention is directed to structurally new polyurethanes andpolyureas made using telechelic PIBs formed from these new initiatorcompositions.

In one or more embodiments, the present invention relates to novel lowcost LC⁺P initiator molecules having a central benzene ring surroundedby from 1 to 3 short bridges of tricyclo compounds (cyclo groups) eachhaving at least one functional group that, in the presence of aFriedel-Crafts acid co-initiator, produce well-defined one, two, orthree arm telechelic polymers. The following structures arerepresentative of these novel low cost LC⁺P initiator molecules:

where each x is Cl, OH, or OCH₃.

In some embodiments, the present invention relates to two novel low costLC⁺P initiator molecules, namely,2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene-4,9-diol(abbreviated herein as bBCB-ol, for bis-benzocyclobutenol), and4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3.6)]deca-1(8),2,6-triene(abbreviated herein as bBdClCB, for bis-benzo-dichloro-cyclobutenol),that initiate bidirectional LC⁺P in the presence of Friedel-Crafts acidco-initiators and produce well-defined two arm telechelic polymers. Itshould be appreciated that the two —CH₃ groups on the phenyl ring inthese and similar embodiments prevent intramolecular aromatic alkylationand enable LC⁺P to proceed.

In some other embodiments, the present invention is directed to thecorresponding alcohol (i.e., the methoxy derivative-X═O) of molecules(VI), (VII), or (VIII), having the following structures:

In still other embodiments, the present invention is directed to thecorresponding alcohol (i.e., the hydroxyl derivative-X═OH) of molecules(VI), (VII), or (VIII), having the following structures:

In still other embodiments, novel low cost LC⁺P initiator moleculesaccording to the present invention may be formed from1,2,3,5-tetramethyl benzene rather than 1,2,4,5-tetramethylbenzene(durene). In one or more of these embodiments, low cost initiatorcompositions of the present invention may include, without limitation,initiator molecules made from 1,2,3,5-tetramethyl benzene or havingsimilar structures. In one or more embodiments, the novel low cost LC⁺Pinitiator molecules according to the present invention may be formedfrom 1,2,3,5-tetramethyl benzene and have one of the followingstructures:

wherein x is Cl, OH, or OCH₃.

In various embodiments, the novel low cost LC⁺P initiator molecules ofthe present invention may have the formula:

In various embodiments, the synthesis of bi-functional initiatorsaccording to various embodiments of the present invention starts withlow cost and readily commercially available reactants, namely1,2,4,5-tetramethylbenzene (durene) or 1,2,3,5-tetramethyl benzene,rather than the much more expensive starting material used for thesynthesis of HDCCl, such as 5-tert-butylisophthalic acid(5-tert-butyl-1,3-benzene-dicarboxylicacid) and does not require the useof “costly reagents,” such as methymagnesium bromide and HCl gas.1,2,4,5-tetramethylbenzene (durene) and 1,2,3,5-tetramethyl benzene arecommercially available from numerous sources including Sigma-Aldrich(St. Louis Mo.), AKos Consulting & Solutions GmbH (Germany), and TokyoChemical Industry Co., Ltd. (TCI) (Japan). Further this process is muchsimpler (i.e. it requires less steps) and consequently it is less costlythan that of HDCCl.

As used herein, the term “bifunctional initiator(s)” or “bifunctionalinitiator molecule” or “bifunctional molecule” are used interchangeablyto refer to an initiator molecule that initiates bidirectional LC⁺P inthe presence of Friedel-Crafts acid co-initiators to producewell-defined two arm telechelic polymers. Likewise, as used herein theterms “monofunctional initiator(s)” or “monofunctional initiatormolecule” or “monofunctional molecule” are used interchangeably to referto an initiator molecule that initiates monodirectional LC⁺P in thepresence of Friedel-Crafts acid co-initiators to produce well-definedsingle arm telechelic polymers. Similarly, as used herein the terms“trifunctional initiator(s)” or “trifunctional initiator molecule” or“trifunctional molecule” are used interchangeably to refer to aninitiator molecule that initiates tridirectional LC⁺P in the presence ofFriedel-Crafts acid co-initiators to produce well-defined three armtelechelic polymers.

Scheme 2 below outlines the syntheses of bBCB-ol and its conversion tobBdClCB and is generally representative of the process:

In Scheme 2, above, the starting material is durene (XXIX), but theinvention is not so limited and suitable starting materials may alsoinclude, without limitation, 1,2,4,5-tetramethyl benzene and1,2,3,5-tetramethyl benzene. The first step involves the Friedel-Craftsdiacylation of the starting material with an acetyl halide, such asacetyl chloride (AcCl), acetyl bromide, or acetic anhydride in thepresence of aluminum chloride (AlCl₃) or a similar Lewis acid, such asFeCl₃ or AlBr₃, in a suitable solvent such as CS₂, dichloromethane,chloroform, chlorobenzene, or nitromathane. (See, e.g., Pinkus A. G.,Kalyanam N., Organic Preparations and Procedures Int, 10 (6), 255, 1978and Andreou A. D., Bulbulian R. V., Gore P. H., Tetrahedron, 36, 2101,1980 the disclosures of which is incorporated herein by reference in itsentirety) and (ii) separating the resulting polymer containing solutioninto organic and aqueous phases, washing the resulting organic phasewith aqueous sodium carbonate (see, Scheme 2) and water, removing thesolvent and drying the resulting product to produce the correspondingdiethanone, 1,1′-(2,3,5,6-tetramethyl-1,4phenylene) diethanone (diacetyldurene, (DAD)) (molecule (XXX) in Scheme 2).

In one or more embodiments, the ratio of AlCl₃/AcCl/starting material(durene) was in the range of 6-7:3-5:1.

In one or more embodiments, the AcCl, AlCl₃, and dry CS₂ were placed (inthis sequence and under a nitrogen atmosphere) in a vessel equipped witha condenser, mechanical stirrer, and three-way valve, heated to refluxand stirred for from about 6 to about 12 hours before the startingmaterial (dissolved in CS₂) was added and stirring continued at refluxfor an additional 10 to 14 hours (overnight). In some embodiments, theAcCl, AlCl₃, and dry CS₂ were heated to reflux and stirred for fromabout 6 to about 10 hours, in other embodiments, from about 7 to about10 hours and in other embodiments, from about 8 to about 9 hours beforethe starting material (dissolved in CS₂) was added. In some embodiments,the AcCl, AlCl₃, dry CS₂ and starting material were stirred at refluxfor from about 2 to about 5 hours, in other embodiments, 4 to about 6hours, in other embodiments, 5 to about 7 hours, in other embodiments, 6to about 8 hours, in other embodiments, 9 to about 11 hours, in otherembodiments, 10 to about 12 hours, in other embodiments, 10 to about 12hours, in other embodiments, from about 12 to about 14 hours and inother embodiments, from about 11 to about 13 hours after the startingmaterial (dissolved in CS₂) was added.

In one or more of these embodiments, the diacetyl durene (XII)containing solution is then separated into organic and aqueous phases bypouring the polymer diacetyl durene solution onto crushed ice,acidifying it with concentrated aqueous hydrochloric acid, and thenadding methylene chloride.

In one or more of these embodiments, after being washed in a aq. sodiumcarbonate (see, Scheme 2), the polymer containing organic phase is thendried over anhydrous sodium sulfate for from about 1.5 to about 4 hours,in other embodiments, from about 2 to about 4 hours, and in otherembodiments, from about 2 to about 3 hours. In one or more of theseembodiments, the solvent may be removed by rotary evaporation and thewhite solid was recrystallized from solvent, such as, diethyl ether or,in other embodiments, benzene (See, Example 1, below). The choice ofrecrystallization solvent will depend upon the particular product beingproduced and one of ordinary skill in the art will be able to select asuitable recrystallization solvent without undue experimentation.

In a second step, the corresponding diethanone molecule (diacetyldurene, (DAD), molecule (XXX) in Scheme 2) is dissolved in a suitablesolvent, such as benzene or tetrahydrofuran (THF) and irradiated withultraviolet light for a period of from about 48 hours to about 96 hoursat a temperature of from about 40° C. to about 60° C. to form thecorresponding bis-benzocyclobutenol. In the embodiment of Scheme 2, thebis-benzocyclobutenol is2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene-4,9-diol(bBCB-ol)(molecule (XXI) in Scheme 2).

In some of these embodiments, diethanone molecule (XXX) may beirradiated with ultraviolet light having a wavelength of from about 290nm to about 340 nm for a period of from about 55 hours to about 96hours. In some embodiments, the diethanone molecule (XXX) may beirradiated with ultraviolet light having a wavelength of from about 290nm to about 330 nm, in other embodiments, from about 290 nm to about 320nm, in other embodiments, from about 290 nm to about 310 nm, in otherembodiments, from about 295 nm to about 330 nm, in other embodiments,from about 295 nm to about 315 nm, and in other embodiments, from about295 nm to about 315 nm. In some embodiments, the diethanone molecule(XXX) may be irradiated with ultraviolet light having a wavelength ofabout 300 nm.

In some embodiments, the diethanone molecule (XXX) may be irradiatedwith ultraviolet light from about 65 hours to about 96, in otherembodiments, from about 75 hours to about 96, in other embodiments, fromabout 48 hours to about 85, and in other embodiments, from about 48hours to about 75. In some of these embodiments, correspondingdiethanone (XXX) may be irradiated with ultraviolet light for at atemperature of from about 45° C. to about 60° C., in other embodiments,from about 50° C. to about 60° C., in other embodiments, from about 55°C. to about 60° C., in other embodiments, from about 40° C. to about 55°C., in other embodiments, from about 40° C. to about 50° C., in otherembodiments, from about 40° C. to about 60° C., and in otherembodiments, from about 45° C. to about 55° C. In some of theseembodiments, the diethanone (XXX) is irradiated with ultraviolet lightfor a period of about 72 hours at a temperature of about 50° C.

In one or more embodiments, this step may be carried out using thephotolysis apparatus 10 shown in FIG. 2. As can be seen, photolysisapparatus 10 shown in FIG. 2 comprises a heating element 12, roundbottom flask 14, reflux condenser 16, a magnetic stirring bar 18, 2 wayvalve 20, and a plurality of UV lamps 22. In the embodiment shown inFIG. 2, the plurality of UV lamps 22 comprises six 9 watt, 300 nm broadband UV lamps.

In some embodiments, the bis-benzocyclobutenol (see, e.g., molecule(XXI) in Scheme 2) may be hydrochlorinated to form the correspondingdichloro compound (see, e.g., molecule (XXIV) in Scheme 2). In theembodiment of Scheme 2, the correspondingbis-benzo-dichloro-cyclobutenol is4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene(XXIV) (bBdClCB). (See, Example 2, below). However, other suitablemethods known in the art for replacing the OH group with a halogen mayalso be used in some embodiments.

In some of these embodiments, the bis-benzocyclobutenol (see, molecule(XXI) in Scheme 2) may be hydrochlorinated using the chlorinationapparatus 30 shown in FIG. 4. As can be seen, the hydrochlorinationapparatus 30 of FIG. 4 comprises a first heating element 32, in thermalcontact with a first reaction vessel 34 having a lower portion 36containing NaCl, an upper portion 38 containing H₂SO₄ and including gasinlet valve 40 through which a dry gas, such as nitrogen gas, enters thesystem, and a valve 42 separating the upper portion 38 and lower portion36. Valve 42 may be opened to allow the H₂SO₄ to flow dropwise into thelower portion 36 and onto the NaCl, where it reacts with the NaCl toproduce HCl gas. In some of these embodiments, the bis-benzocyclobutenol(see, e.g., molecule (XXI) in Scheme 2) is dissolved in a suitablesolvent such as dichloromethane (CH₂Cl₂) and placed in a second reactionvessel 44 containing CaCl₂. Second reaction vessel 44 is in thermalcontact with a second heating element 46. A first Teflon capillary tube48 runs from the lower portion 36 of the first reaction vessel 34 andinto second reaction vessel 44. In these embodiments, the HCl gasgenerated in the reaction vessel 34 is allowed to flow through the firstTeflon™ capillary tube 48 into the second reaction vessel 44 and bubblethrough its contents. The HCl gas then flows out of the second reactionvessel 44 through a second Teflon™ capillary tube 50 into a first flask52 and then through a third Teflon capillary tube 54 into a second flask56 containing aqueous NaOH, where it is neutralized.

In one or more of these embodiments, the gaseous HCl is bubbled into thebis-benzocyclobutenol solution in the presence of CaCl₂ for from about 4hours to about 8 hours at a temperature of from about −10° C. to about10° C. under continuous nitrogen flush. In some embodiments, the gaseousHCl is bubbled into the bis-benzocyclobutenol solution in the presenceof CaCl₂ from about 4 hours to about 7 hours, in other embodiments, fromabout 4 hours to about 6 hours, and in other embodiments, from about 6hours to about 8 hours under continuous nitrogen flush. In some of theseembodiments, the gaseous HCl is bubbled into the bis-benzocyclobutenolsolution at a temperature of from about −10° C. to about 10° C., inother embodiments, from about −7° C. to about 7° C., and in otherembodiments, from about −3° C. to about 3° C. In some of theseembodiments, the gaseous HCl was bubbled into the bis-benzocyclobutenolsolution in the presence of CaCl₂ for six hours at 0° C. undercontinuous nitrogen flush. In these embodiments, the CaCl₂ is removed byfiltration and the corresponding dichloro compound (see, e.g., molecule(XXIV) in Scheme 2) is then extracted, dried, and purified according toestablished methods. (See, Example 3, below).

It is believed that this same strategy can also be used to prepare mono-and tri-functional initiators As used herein, the term “monofunctionalinitiator(s)” or “monofunctional initiator molecule” or “monofunctionalmolecule” are used interchangeably to refers to an initiator moleculethat instantaneously initiates monodirectional LC⁺P in the presence ofFriedel-Crafts acid co-initiators to produce well-defined single armtelechelic polymers. Likewise, as used herein, the term “trifunctionalinitiator(s)” or “trifunctional initiator molecule” or “trifunctionalmolecule” are used interchangeably to refers to an initiator moleculethat instantaneously initiates tridirectional LC⁺P in the presence ofFriedel-Crafts acid co-initiators to produce well-defined single armtelechelic polymers.

Suitable starting materials for production of monofunctional initiatorsusing the strategy described above include, without limitation,mono-acetylated durene. Similarly, and as shown in Scheme 3 below,suitable starting materials for production of new trifunctionalinitiators (for preparation of tri-arm star polymers) using the strategydescribed above include, without limitation, triacetylated1,3,5-trimethylbenzene (mesitylene).

where each x is Cl, OH, or OCH₃.

As set forth above, it is believed that the low cost novel initiators ofthe present invention can be used in place of prior art LC⁺P initiatorsto make a wide variety of polymers. It should also be appreciated thatbecause these novel initiators, in conjunction with Friedel-Craftsacids, are sources of highly reactive tert carbocations (see Scheme 4,below) they will initiate the polymerization of any cationic monomerknown to the art including but not limited to, isobutylene styrenes,butadiene, isoprene, cyclopentadiene, pinenes, and vinylether. (See J.P. Kennedy, Cationic Polymerization of Olefins: A Critical Inventory,Wiley/Interscience pub. 1975, the disclosure of which is incorporatedherein by reference in its entirety.) It is believed that the low costnovel initiators of the present invention can be substituted 1 for 1with the initiators currently in use (including, but not limited tothose initiators described in U.S. Pat. Nos. 5,733,998 and 8,889,926,the disclosure of which are incorporated herein by reference in theirentirety) for any LC⁺P reaction producing one, two, or three armpolymers. Furthermore, as these novel initiators become incorporatedinto the polymers they produce, it is believed that the structures theyproduce are also novel.

Importantly, in a variety of embodiments, the initiator molecules of thepresent invention may be used to form functionalized telechelicpolyisobutylene compositions comprising one, two, or threepolyisobutylene chains extending from the residue of the initiatormolecule, each chain having a terminal functional group. A wide varietyof terminal functional groups may be added to these telechelicpolyisobutylene compositions using conventional techniques. Suitableterminal functional groups may include, without limitation, allylgroups, hydroxyl groups, primary alcohols, halides, amine groups, azidegroup, thiol group, furanyl group, alkynyl group, cyano group, or acombination thereof.

The low cost bifunctional initiators of the present invention areparticularly useful as a substitute for5-tert-butyl-1,3-bis(1-chloro-1-methylethyl)benzene (HDCCl) (molecule(I)) in the formation of bidirectional telechelic PIB polymers and theirderivative polyurethanes and polyureas. In a variety of embodiments, thepresent invention also includes allyl di-telechelic PIB polymers, halidedi-telechelic PIB polymers, amine di-telechelic PIB polymers,alcohol/amine di-telechelic PIB polymers, polyurethanes, and polyureascontaining the residue of the low cost bifunctional initiators describedabove, including, but not limited to, bBCB-ol, and bBdClCB. It isbelieved that these compounds and polymers can be synthesized usingknown methods simply by substituting the low cost bifunctionalinitiators described above, including, but not limited to, bBCB-ol, andbBdClCB for HDCCl, on a 1 to 1 mole basis. In one or more embodiment,allyl di or tri-telechelic PIB polymers, halide di or tri-telechelic PIBpolymers, amine di or tri-telechelic PIB polymers, polyurethanes, andpolyureas according to various embodiments of the present invention maybe synthesized as set forth in U.S. Pat. Nos. 8,552,118, 8,674,034, and9,359,465; U.S. Published Patent Application Nos. 2013/0331538 and2015/0191566; and International Patent Application No. WO 2010/039986,the disclosures of which are incorporated herein by reference in theirentirety, by substituting the appropriate low cost bifunctionalinitiator (including, but not limited to, bBCB-ol and bBdClCB) andtrifunctional initiator of the present invention as described above, forthe initiators used therein (including but not limited to thoseinitiators described in U.S. Pat. Nos. 5,733,998 and 8,889,926, thedisclosure of which are incorporated herein by reference in theirentirety), on a 1 to 1 mole basis.

Further while the low cost bifunctional initiators of the presentinvention are particularly useful in the formation of bidirectionaltelechelic PIB polymers, they may also be used to form bidirectionaltelechelic polystyrenes, polyurethane, polyurea, and structurally newdi-block (e.g., PIB-Polystyrene (PSt)) and tri-block (e.g., PSt-PIB-PSt)polymers using known reaction mechanisms. In one or more embodiments,PIB-polystyrene block co-polymers according to the present invention maybe synthesized as shown in Example 12, below. Accordingly, in a varietyof embodiments, the present invention also includes diblock and triblockpolymers comprising PIB, polyurethane, polystyrene, or polyurea blocksthat contain the residue of the low cost bifunctional initiatorsdescribed above, including, but not limited to, bBCB-ol and bBdClCB. Itis believed that these polymers can be synthesized using known methodssimply by substituting the low cost bifunctional initiators describedabove, including, but not limited to, bBCB-ol and bBdClCB, for HDCCl ona 1 to 1 mole basis.

Further, the polymers produced by bBCB-ol or bBdClCB, in particular,contain initiator residues that are valuable sites for furtherderivatizations and thus for the creation of useful new products. Invarious embodiments, the novel initiators of the present invention,including but not limited to bBCB-ol or bBdClCB, may be used to form PIBpolymers with a variety of useful end groups, including withoutlimitation, allyl groups, hydroxyl groups, primary or tertiary alcohols,halides, amine groups, azide groups, thiol groups, furanyl groups,alkynyl groups, cyano groups, and combinations thereof. It is believedthat these polymers may be synthesized using by conventional methods bysubstituting a novel initiator of the claimed invention for theconventional initiator molecule. And because these molecules contain thenovel initiators of the present invention, it is believed that thesemolecules too are novel.

Importantly, low cost bifunctional initiators of the present inventioncan be used to form allyl telechelic PIB polymers. As will be apparentto those of skill in the art, allyl telechelic PIB is a key intermediatefor the synthesis of primary alcohol telechelic PIB (HO—PIB—OH), whichis in turn the key intermediate for the preparation of PIB-basedpolyurethanes. The conversion of allyl telechelic PIB to HO-PIB-OH hasbeen described (see, e.g., U.S. Pat. Nos. 8,552,118 and 9,359,465; U.S.Published Patent Application No. 2015/0191566; and International PatentApplication No. WO 2010/039986, the disclosures of which areincorporated herein by reference in their entirety), together with useof HO-PIB-OH for the synthesis of PIB-PUs. (See, e.g., U.S. Pat. Nos.8,552,118, 8,674,034, and 9,359,465; U.S. Published Patent ApplicationNos. 2013/0331538 and 2015/0191566; and International Patent ApplicationNo. WO 2010/039986, the disclosures of which are incorporated herein byreferenced in their entirety). The inventors are unaware, however, ofany publication or patent teaching the use of2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene-4,9-diol(bBCB-ol) (XXI) or4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene(bBdClCB) (XXIV) as cationogens for the preparation of allyl telechelicPIB or for the initiation of cationic polymerization.

Scheme 4 below outlines a route to allyl telechelic PIB starting withbBCB-ol and bBdClCB:

where n is the number of isobutylene molecules that react to form thePIB chains and m is the number forming one of the two PIB chains. In oneor more embodiments, n is an integer from 4 to about 10,000, or fromabout 14 to about 9,000, or from about 20 to about 8,000, or from about30 to about 7,000, or from about 50 to about 6,000, or from about 150 toabout 5,000, or from about 200 to about 4,000, or from about 500 toabout 3,000, or even from about 1,000 to about 2,000. In one or moreembodiments, m is an integer from 2 to about 5,000, or from about 7 toabout 4,500, or from about 10 to about 4,000, or from about 15 to about3,500, or from about 25 to about 3,000, or from about 75 to about 2,500,or from about 100 to about 2,000, or from about 250 to about 1,500, oreven from about 500 to about 1,000. As will be apparent, in embodimentswhere the molecular weight distribution is narrow, it may be assumedthat values of n and n-m are almost equal. Here, as well as elsewhere inthe specification and claims, individual range limits can be combined toform alternative non-disclosed range limits. (See Examples 4 and 5,below) Except for the use of the new low cost initiator, this route toallyl telechelic PIB is identical to that used earlier with the HDCClinitiator. (See, e.g., U.S. Pat. Nos. 8,552,118, 8,674,034, and9,359,465; U.S. Published Patent Application Nos. 2013/0331538 and2015/0191566; and International Patent Application No. WO 2010/039986,the disclosures of which are incorporated herein by reference in theirentirety).

In these embodiments, a suitable solvent or co-solvent mixture and aproton trap are combined in a suitable reaction vessel and cooled to atemperature of from about −50° C. to about −90° C. In variousembodiments, suitable solvents or co-solvents combinations may include,without limitation, hexane/CH₂Cl₂ (60/40), CH₂Cl₂, CHCl₃, or CH₃Cl. Inone or more embodiments, the proton trap may be DtBP, TMEDA, or DtBPwith TMEDA. In some embodiments, the combination may be cooled to atemperature of from about −50° C. to about −80° C., in otherembodiments, from about −50° C. to about −70° C., in other embodiments,from about −50° C. to about −60° C., in other embodiments, from about−60° C. to about −90° C., in other embodiments, from about −70° C. toabout −90° C., in other embodiments, from about −80° C. to about −90°C., in other embodiments, from about −60° C. to about −90° C. and inother embodiments, from about −75° C. to about −85° C. Under strongstirring bBdClCB and/or bBCB-ol are then added to the reaction vesseland the system stirred for from about 5 min. Then isobutylene (IB) isadded followed by the addition of a Friedel-Crafts acid, such as TiCl₄.In these embodiments, the polymerization is allowed to proceed for from50 to 70 min before being terminated with an allyl silane such astrimethylallylsilane (ATMS) to introduce a terminal allyl group. In someof these embodiments, polymerization is allowed to proceed for from 10to 20 min, in other embodiments, from 10 to 30 min, in otherembodiments, from 10 to 40 min, in other embodiments, from about 10 to60 min, in other embodiments, from about 10 to 70 min, in otherembodiments, from about 20 to 70 min, and in other embodiments, fromabout 45 to 65 min, before being terminated. In some of theseembodiments, the polymerization was allowed to proceed 60 min and wasterminated with 2.4 mL (1.5×10⁻² mol) distilled and prechilledallyltrimethylsilane (ATMS). As will be appreciated, the ATMS serves toadd the terminal allyl group to the PIB chains to form molecule (XVIII).

In some other embodiments, the chlorine terminated PIB isdehydrohalogenated to form an exo olefin group by refluxing it withpotassium tertiary butoxide, as described in U.S. Pat. No. 4,342,849 toKennedy et al., the disclosure of which in incorporated herein byreference in its entirety. In still other embodiments, in-situ quenchingof quasi-living polymerization of isobutylene with1,2,2,6,6-pentamethylpiperidine gives exo olefine terminated PIB asdescribed in Simison, K. L., Stokes, C. D. Harrison, J. J., Storey, R.F., Macromolecules 39(7), 2481, (2006), the disclosure of which inincorporated herein by reference in its entirety.

The system is then stirred for from about 20 to 40 min before methanolis added to fully terminate the polymerization and to decompose theTiCl₄ and the system allowed to warm to room temperature. In some ofthese embodiments, the system is stirred for from 20 to 30 min, in otherembodiments, from about 30 to 40 min, and in other embodiments, fromabout 25 to 35 min, before the methanol is added. In some of theseembodiments, system is then stirred for about 30 min before the methanolis added. The resulting allyl telechelic PIB may be collected andpurified using any conventional means known in the art. In someembodiments, the solution is concentrated by rotary evaporation,precipitated into methanol, the methanol was decanted, the polymerdissolved in hexane, and washed with 5% aqueous sodium bicarbonate andwater. The organic phase is then dried over night over magnesiumsulfate, and filtered through fine sintered glass. Finally, the solventis evaporated by rotary evaporation and the allyl telechelic PIB, acolorless viscous mass, is dried in high vacuum.

In one or more embodiments, the allyl telechelic PIB may have thestructure:

where n is an integer from 4 to about 10,000, or from about 14 to about9,000, or from about 20 to about 8,000, or from about 30 to about 7,000,or from about 50 to about 6,000, or from about 150 to about 5,000, orfrom about 200 to about 4,000, or from about 500 to about 3,000, or evenfrom about 1,000 to about 2,000. In one or more embodiments, m is aninteger from 2 to about 5,000, or from about 7 to about 4,500, or fromabout 10 to about 4,000, or from about 15 to about 3,500, or from about25 to about 3,000, or from about 75 to about 2,500, or from about 100 toabout 2,000, or from about 250 to about 1,500, or even from about 500 toabout 1,000. Here, as well as elsewhere in the specification and claims,individual range limits can be combined to form alternativenon-disclosed range limits.

The following equations describe further processes and compounds thatcan be produced via various embodiments of the present invention. As ageneral rule, all of the following reactions can be run at a 95% orbetter conversion rate.

(A) Cationic living isobutylene polymerization affords a firstintermediate which is, for example, a tert-Cl-terminated PIB chain:˜˜˜C(CH₃)₂—[CH₂—C(CH₃)₂]_(n)—CH₂—C(CH₃)₂—Cl  (A)where ˜˜˜ represents the remaining portion of a one, two, or three armmolecule containing a residue of one of the low cost initiators of thepresent invention as described above and n is an integer from 2 to about5,000, or from about 7 to about 4,500, or from about 10 to about 4,000,or from about 15 to about 3,500, or from about 25 to about 3,000, orfrom about 75 to about 2,500, or from about 100 to about 2,000, or fromabout 250 to about 1,500, or even from about 500 to about 1,000. Here,as well as elsewhere in the specification and claims, individual rangelimits can be combined to form alternative non-disclosed range limits.

As would be apparent to those of skill in the art, ˜˜˜ can in someinstances represent another chlorine atom in order to permit theproduction of substantially linear di-terminal primary alcohol PIBs ortwo other chlorine atoms in order to permit the production of starshaped tri-terminal primary alcohol PIBs using this method. As will beappreciated by those of skill in the art, all of the PIB chains areformed substantially simultaneously. Additionally, it should be notedthat the present invention is not limited to the above specific linkinggroups (i.e., the —C(CH₃)₂) between the repeating PIB units and theremainder of the molecules of the present invention.

The next step is the dehydrchlorination of (A) to afford the secondintermediate shown below:˜˜˜C(CH₃)₂—[CH₂—C(CH₃)₂]_(n)—CH₂—C(CH₃)═CH₂  (B).The dehydrochlorination of (A) may be accomplished according to anymethod known in the art for that purpose. In some embodiments, thechlorine terminated PIB may be dehydrohalogenated to form exo olefingroup by refluxing 20 hours with potassium tertiary butoxide, cooling,water washing repeatedly, and drying as shown in U.S. Pat. No. 4,342,849to Kennedy, the disclosure of which is incorporated herein by referencein its entirety, and shown in Scheme 5 below

where n is an integer from 4 to about 10,000, or from about 14 to about9,000, or from about 20 to about 8,000, or from about 30 to about 7,000,or from about 50 to about 6,000, or from about 150 to about 5,000, orfrom about 200 to about 4,000, or from about 500 to about 3,000, or evenfrom about 1,000 to about 2,000. In one or more embodiments, m is aninteger from 2 to about 5,000, or from about 7 to about 4,500, or fromabout 10 to about 4,000, or from about 15 to about 3,500, or from about25 to about 3,000, or from about 75 to about 2,500, or from about 100 toabout 2,000, or from about 250 to about 1,500, or even from about 500 toabout 1,000. Here, as well as elsewhere in the specification and claims,individual range limits can be combined to form alternativenon-disclosed range limits.

The third step is the anti-Markovnikov hydrobromination of (B) to affordthe primary bromide shown below:˜˜˜C(CH3)2-[CH2-C(CH3)2]n-CH2-CH(CH3)-CH2-Br  (C).The hydrobromination of (B) may be accomplished according to any methodknown in the art for that purpose provided. In some embodiments,hydrobromination of (B) may be accomplished by bubbling first air for 30minutes and then HBr gas through a solution containing (B) for 10minutes as known in the art for that purpose. In some embodiments, the(B) may be hydrobromated as shown in Scheme 6.

where n and m are as set forth above.

The fourth step is the conversion of the primary bromide by the use of abase (e.g., NaOH, KOH, or tert-BuONa) as shown in Scheme 7 below to aprimary hydroxyl group according to the following formula:˜˜˜C(CH₃)₂—[CH₂—C(CH₃)₂]_(n)—CH₂—CH(CH₃)—CH₂—OH  (D).The conversion of the primary bromide of (C) to a primary hydroxyl groupmay be accomplished according to any method known in the art for thatpurpose. In some embodiments, conversion of the primary bromide of (C)to a primary hydroxyl group may be accomplished by nucleophilicsubstitution on the bromine with the addition of an aqueous solution ofNaOH. Optionally, a phase transfer catalyst such as tetraethyl ammoniumbromide can be added to speed up the reaction.

where n and m are as set forth above.

In another embodiments, the following reaction steps can be used toproduce a primary alcohol-terminated PIB compound according to thepresent invention.

Instead of the dehydrochlorination, as outlined in (B) above, one canuse an allyl silane such as trimethyl allyl silane to prepare an allylterminated PIB (See e.g., Scheme 4, above):˜˜˜C(CH₃)₂—[CH₂—C(CH₃)₂]_(n)—CH₂—CH═CH₂  (B′).Suitable allyl silanes may include, without limitation, trimethyl allylsilane.

Similarly to the reaction shown in (C) above, the (B′) intermediate isconverted to the primary bromide by an anti-Markovnikov reaction(hydrobromination of the terminal allyl groups) to yield the followingcompound:˜˜˜C(CH₃)₂—[CH₂—C(CH₃)₂]_(n)—CH₂—CH₂—CH₂—Br  (C′).

(C′) can be converted to a primary alcohol-terminated compound asdiscussed above to yield the following compound:˜˜˜C(CH₃)₂—[CH₂—C(CH₃)₂]_(n)—CH₂—CH₂—CH₂—OH  (D′).

In still other embodiments, bis-hydroxy telechelic PIB according to thepresent invention may be made according to the two step reaction shownin Scheme 8.

where n and m are as set forth above. In one or more embodiments, thealcohol di-telechelic PIB may have the structure:

where each individual n is an integer from 2 to about 5,000, or fromabout 7 to about 4,500, or from about 10 to about 4,000, or from about15 to about 3,500, or from about 25 to about 3,000, or from about 75 toabout 2,500, or from about 100 to about 2,000, or from about 250 toabout 1,500, or even from about 500 to about 1,000. Here, as well aselsewhere in the specification and claims, individual range limits canbe combined to form alternative non-disclosed range limits.

In one embodiment, the primary alcohols that can be used as terminatinggroups in the present invention include, but are not limited to, anystraight or branched chain primary alcohol substituent group having from1 to about 12 carbon atoms, or from 1 to about 10 carbon atoms, or from1 to about 8, or from about 1 to about 6 carbon atoms, or even fromabout 2 to about 5 carbon atoms. Here, as well as elsewhere in thespecification and claims, individual range limits can be combined toform alternative non-disclosed range limits.

In some other embodiments, low cost bifunctional initiators of thepresent invention may also be used to form novel amine terminated PIBpolymers. In one or more embodiments, the novel amine terminated PIBpolymers may have the following formula:

wherein each n is an integer from 2 to about 5,000. In some embodiments,each n may be an integer from 2 to about 4,500, or from about 7 to about4,500, or from about 10 to about 4,000, or from about 15 to about 3,500,or from about 25 to about 3,000, or from about 75 to about 2,500, orfrom about 100 to about 2,000, or from about 250 to about 1,500, or evenfrom about 500 to about 1,000. Here, as well as elsewhere in thespecification and claims, individual range limits can be combined toform alternative non-disclosed range limits.

These novel amine terminated PIB polymers may be formed using any knownmethod wherein the novel initiator of the present invention describedabove is substituted for the initiator ordinarily used. These novelamine terminated PIB polymers may be formed according to any of themethods for doing so described in U.S. Pat. Nos. 8,552,118 and9,359,465, the disclosures of which are incorporated herein by referencein their entirety, where one of the novel initiator of the presentinvention is substituted for the HDCCl initiator. In some embodiments,novel amine terminated PIB polymers of the present invention may be madeas set forth in Scheme 9 below:

In these embodiments, allyl terminated PIB (X) is converted to the novelamine terminated PIB (XII) polymer in three steps: (a) hydrobromation ofthe allyl terminated PIB (X) with HBr gas as described above to producethe terminal primary bromine terminated PIB (XL); (b) substitution ofthe terminal primary bromine to phthalimide-terminated polyisobutylene(PIB—(CH₂)₃-phthalimide) by reacting it with potassium pthalimide; and(c) hydrazinolysis of the phthalimide terminated polyisobutylene toprimary amine-terminated polyisobutylene (XII).

In various embodiments, synthesis of a phthalimide-terminatedpolyisobutylene may be carried out according to Scheme 10 shown below:

where * is the remainder of the molecule and n is an integer from 2 toabout 5000.

In one or more of these embodiments, the bromine terminated PIB (XLI) isdissolved in a suitable solvent such as THF and N-methyl-2-pyrrolidone(NMP) is added to increase the polarity of the medium. Potaisumphthalimide (XLII) is then added to the solution and it is refluxed at atemperature of from about 70° C. to about 90° C. for from about 3 to 5hours. The reaction mixture is then diluted by the addition of hexaneand washed with excess water. The organic layer is separated, washedthree with distilled water, and dried over MgSO₄. The hexane is removedby a rotory evaporation (rotovap), and the resulting phthalimideterminated PIB polymer (XLIII) is dried under vacuum.

In one or more embodiments, synthesis of an amine-terminated PIB (XLIV)from the phthalimide terminated PIB (XLIII) may be carried out accordingScheme 11 shown below:

where * is the remainder of the molecule and n is an integer from 2 toabout 5000. In some of these embodiments, the phthalimide terminated PIB(XLIII) is dissolved in a mixture of heptane and ethanol, and hydrazinehydrate is added. This mixture is then refluxed at from about 100° C. toabout 110° C. for about 4-6 hours. The charge is the diluted with hexaneand washed with excess water. The organic layer is then separated,washed with distilled water. and dried over MgSO₄. The hexane is removedby a rotory evaporation (rotovap), and the resulting amine terminatedPIB (XLIV) polymer is dried under vacuum.

As noted above, the primary alcohol-terminated PIBs are usefulintermediates in the preparation of polyurethanes by reaction viaconventional techniques, i.e., by the use of known isocyanates,including but not limited to 4,4′-methylenediphenyl diisocyanate, (MDI)and 4,4′-methylene dicyclohexyl diisocyanate (HMDI), known chainextension agents including, but not limited to 1,4-butane diol (BDO),1,6-hexane diol (HDO) and/or 1,6-hexane diamine (HDA), and a catalyst.As set forth above, polyurethanes according to various embodiments ofthe present invention may be synthesized as set forth in U.S. Pat. Nos.8,552,118, 8,674,034, and 9,359,465, the disclosures of which areincorporated herein by reference in their entirety, by substituting theappropriate low cost bifunctional initiator (including, but not limitedto, bBCB-ol and bBdClCB) of the present invention as described above,for the initiators used therein on a 1 to 1 mole basis.

A great advantage of these polyurethanes (PUs) is their outstandinghydrolytic and oxidative and biological stability imparted by the stablePIB segment. Moreover, since PIB is known to be biocompatible, any PUmade from the PIB compounds of the present invention is novel as well asbiocompatible.

In one or more embodiments, the PIB polyurethane comprising the residueof the novel low cost difunctional initiator of the present inventionmay have the structure:

where each n is an integer from 2 to about 5,000; m is is an inter from2 to about 1,000,000; and R is the residue of a diisocyanate. In variousembodiments, R may be the residue of toluene diisocyanate or 4,4′-diphenylmethane diisocyanate. In some embodiments, R may the formula:

In one or more of these embodiments, each n may be an integer in therange of from 2 to about 4,500, or from about 7 to about 4,500, or fromabout 10 to about 4,000, or from about 15 to about 3,500, or from about25 to about 3,000, or from about 75 to about 2,500, or from about 100 toabout 2,000, or from about 250 to about 1,500, or even from about 500 toabout 1,000. In one or more embodiments, each m may be an integer from 2to 900,000, in other embodiments, from 2 to 700,000, in otherembodiments, from 2 to 500,000, in other embodiments, from 2 to 400,000in other embodiments, from 2 to 200,000, in other embodiments, from 100to 1,000,000, in other embodiments, from 1000 to 1,000,000, in otherembodiments, from 10,000 to 1,000,000, in other embodiments, from100,000 to 1,000,000, in other embodiments, from 300,000 to 1,00,000,and in other embodiments, from 500,000 to 1,000,000. Here, as well aselsewhere in the specification and claims, individual range limits canbe combined to form alternative non-disclosed range limits.

As also noted above, the amine-terminated PIBs are useful intermediatesin the preparation of polyureas by reaction via conventional techniques,i.e., by the use of known isocyanates, including but not limited to4,4′-methylenediphenyl diisocyanate, (MDI) and 4,4′-methylenedicyclohexyl diisocyanate (HMDI). As set forth above, polyurea accordingto various embodiments of the present invention may be synthesized asset forth in U.S. Pat. No. 8,552,118, and 9,359,465, the disclosures ofwhich are incorporated herein by reference in their entirety, bysubstituting the appropriate low cost bifunctional initiator (including,but not limited to, bBCB-ol and bBdClCB) of the present invention asdescribed above, for the initiators used therein on a 1 to 1 mole basis.

In one or more embodiments, the present invention is directed to a PIBbased polyuria comprising the residue of the novel low cost difunctionalinitiator of the present invention may have the structure:

where each n is an integer from 2 to about 5,000; m is is an inter from1 to about 1,000,000; and R is the residue of a diisocyanate. In variousembodiments, R may be the residue of toluene diisocyanate or 4,4′-diphenylmethane diisocyanate. In some embodiments, R may the formula:

In one or more of these embodiments, each n may be an integer in therange of from 2 to about 4,500, or from about 7 to about 4,500, or fromabout 10 to about 4,000, or from about 15 to about 3,500, or from about25 to about 3,000, or from about 75 to about 2,500, or from about 100 toabout 2,000, or from about 250 to about 1,500, or even from about 500 toabout 1,000. In one or more embodiments, each m may be an integer from 2to 900,000, in other embodiments, from 2 to 700,000, in otherembodiments, from 2 to 500,000, in other embodiments, from 2 to 400,000in other embodiments, from 2 to 200,000, in other embodiments, from 100to 1,000,000, in other embodiments, from 1000 to 1,000,000, in otherembodiments, from 10,000 to 1,000,000, in other embodiments, from100,000 to 1,000,000, in other embodiments, from 300,000 to 1,00,000,and in other embodiments, from 500,000 to 1,000,000. Here, as well aselsewhere in the specification and claims, individual range limits canbe combined to form alternative non-disclosed range limits.

As will be apparent, primary alcohol-terminated PIBs andamine-terminated PIBs of various embodiments of the present inventionare also useful intermediates in the formation of polyurethane ureas byreaction via conventional techniques by substituting the appropriate lowcost bifunctional initiator (including, but not limited to, bBCB-ol andbBdClCB) of the present invention as described above, for the initiatorsused therein on a 1 to 1 mole basis. In one or more embodiments, thepolyurethane ureas according to the present invention may be made usingthe methods described in U.S. Published Application Number 1023/033,538,U.S. Published Application Number 2015/0191566, U.S. PublishedApplication Number 2011/0213084, and U.S. Pat. No. 8,674,034, all ofwhich are incorporated herein by reference.

EXAMPLES

The following examples are offered to more fully illustrate theinvention, but are not to be construed as limiting the scope thereof.Further, while some of examples may include conclusions about the waythe invention may function, the inventor do not intend to be bound bythose conclusions, but put them forth only as possible explanations.Moreover, unless noted by use of past tense, presentation of an exampledoes not imply that an experiment or procedure was, or was not,conducted, or that results were, or were not actually obtained. Effortshave been made to ensure accuracy with respect to numbers used (e.g.,amounts, temperature), but some experimental errors and deviations maybe present. Unless indicated otherwise, parts are parts by weight,molecular weight is weight average molecular weight, temperature is indegrees Centigrade, and pressure is at or near atmospheric.

Example 1 Synthesis of Diacetyl Durene (DAD)

Friedel-Crafts diacylation of durene was carried out by a proceduredescribed in the literature with acetyl chloride (AcCl) in the presenceof aluminum chloride (AlCl₃) and CS₂ solvent (Pinkus A. G., Kalyanam N.,Organic Preparations and Procedures Int, 10 (6), 255, 1978). The ratioof AlCl₃/AcCl/durene we used was approximately 6:3:1.

Thus, in a 500 mL round bottom flask equipped with a condenser,mechanical stirrer, and three-way valve, under a nitrogen atmosphere,were placed AcCl (13 g, 0.16 moles), AlCl₃ (34 g, 0.25 moles), and 70 mLdry CS₂ (in this sequence), the system was heated to reflux and stirredfor ˜8 hrs. To the refluxing stirred solution was slowly added durene (5g, 0.037 moles) dissolved in 50 mL CS₂, and stirring was continued atreflux overnight. That reaction was taking place was indicated by theoriginally yellow solution turning red. Then the content of the flaskwas poured onto crushed ice, and the system was acidified by dropwiseaddition of concentrated aqueous hydrochloric acid. Methylene chloride(˜100 mL) was added and the aqueous and organic phases were separated.The aqueous phase was washed twice with ˜60 mL portions of methylenechloride, and the washings were combined with the organic phase. Thenthe organic phase was washed with aqueous sodium carbonate (10%),distilled water, and dried over anhydrous sodium sulfate for ˜2 hrs. Thesolvent was removed by rotary evaporation and the white solid wasrecrystallized from benzene. Yield 90% of DAD. Mp 177° C. FIG. 1 showsthe ¹H NMR spectrum of DAD. H¹NMR (CDCl₃): δ=2.08 ppm (s, 12H, a),δ=2.44 ppm (s, 6H, b).

Example 2 Synthesis of 2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene-4,9-diol (bBCB-ol)

A 300 mL Pyrex flask equipped with a magnetic stir bar and refluxcondenser, containing diacetyl durene in benzene solution (7.45×10⁻³M)under a nitrogen atmosphere was placed in a UV chamber. The solution wasstirred and irradiated with six 9 W, 300 nm broad band UV lamps (PhilipsUVB Broad Band PL-S 9 W/12) for 72 hrs at 50° C., using the apparatusshown in FIG. 2. Subsequently, the solvent was evaporated, and thebBCB-ol, a white solid, was characterized by ¹H NMR spectroscopy (FIG.3). H¹NMR (CDCl₃): δ=1.67 ppm (s, 6H, a), δ=2.14 ppm (s, 6H, b), δ=2.13ppm (s, 2H, c), δ=3.02, 3.05, 3.17, 3.20 ppm (s, 4H, d)

Example 3 Synthesis of4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene(bBdClCB)

bBCB-ol was chlorinated using the apparatus shown in FIG. 4. bBCB-ol(0.1 g, 7×10⁻⁴ moles) in a Schlenk flask was dissolved in methylenechloride (50 mL) under a nitrogen atmosphere and the solution wastransferred by stainless steel capillary into a flame dried 100 mLtubular reactor containing CaCl₂. Gaseous HCl (generated by dropwiseaddition of sulfuric acid onto NaCl) was bubbled into the solution byTeflon capillary tubing for six hours at 0° C. under continuous nitrogenflush. Excess HCl was neutralized by letting the gas through aqueoussodium hydroxide (See FIG. 4). The CaCl₂ was filtered off using a finesintered glass filter, the solution was concentrated by rotaryevaporation, diluted with 50 mL diethyl ether, and washed with 5%aqueous sodium bicarbonate and water. The diethyl ether layer wasseparated, dried over MgSO₄, the drying agent was filtered off, and thesolvents were removed under reduced pressure. The bBdClCB, a whitesolid, was stored under nitrogen at −20° C. FIG. 5 shows the ¹H NMRspectrum of bBdClCB. H¹NMR (CDCl₃): δ=1.97 ppm (s, 6H, a), δ=2.13 ppm(s, 6H, b), δ=3.33 ppm, 3.36 ppm, 3.48 ppm, 3.51 ppm (s, 2H, c)

Example 4 Synthesis of allyl telechelic PIB with bBdClCB

The synthesis of allyl telechelic PIB was carried out by thewell-established procedure for the synthesis of telechelic PIBs (Ivan,B., Kennedy, J. P. Polym. Mater. Sci. 58, 866 (1988); Ivan, B., Kennedy,J. P. J. Polym. Sci., Part A: Polym. Chem. 28, 89 (1990)), except weused the novel initiator bBdClCB in place of HDCCl.

Thus, into a 300 mL round bottom flask equipped with a magnetic stirrerwas placed 30 mL dried and distilled hexane, 20 mL dried and distilleddichloromethane and DtBP (5.0×10⁻⁵ mol) proton trap and cooled to −80°C. Under strong stirring 7.7×10⁻² g (3.0×10⁻⁴ mol) bBdClCB was added andthe system stirred for 5 min. Then 4.6 mL (5.3×10⁻² mol) IB was addedfollowed by the addition of 0.7 mL (6.0×10⁻³ mol) TiCl₄. Thepolymerization was allowed to proceed 60 min and was terminated with 2.4mL (1.5×10⁻² mol) distilled and prechilled allyltrimethylsilane (ATMS).After 30 min of stirring ˜5 mL methanol was added to terminate thepolymerization and to decompose the TiCl₄. The reactor was removed fromthe cooling bath and allowed to warm to room temperature. The solutionwas concentrated by rotary evaporation, precipitated into ˜100 mLmethanol, the methanol was decanted, the polymer dissolved in hexane,and washed with 5% aqueous sodium bicarbonate and water. The organicphase was dried over night over magnesium sulfate, and filtered throughfine sintered glass. Finally, the solvent was evaporated by rotaryevaporation and the allyl telechelic PIB, a colorless viscous mass, wasdried in high vacuum.

The allyl telechelic PIB was characterized by ¹H NMR spectroscopy andGPC (FIGS. 6 and 7, respectively). ¹H NMR (CDCl₃): δ=1.03-1.22 ppm (br,6H, a), 1.35-1.46 ppm (br, 2H, b), 5.6-6.0 ppm(br, H, c), 4.75-5.20 ppm(br, 2H,d); Mn,_(1H NMR)=11 850 g/mol. (FIG. 6). Mn,_(1H NMR) wascalculated from the integrals of backbone methyl protons (—C(CH₃)₂—, δ1.03-1.22) relative to the methylene protons or methine proton of theallyl group (═CH—, δ 4.80-5.15, and ═CH₂, δ 5.70-6.00). According toGPC, Mn,_(GPC)=10,360 g/mol (polystyrene standards) and Mw/Mn=1.18 (FIG.7).

Example 5 Synthesis of allyl telechelic PIB with bBCB-ol

Thus, into a 500 mL round bottom flask equipped with a magnetic stirrerwas placed 60 mL dried and distilled hexane, 40 mL dried and distilleddichloromethane and DtBP (1.0×10⁻⁴ mol) proton trap and cooled to −80°C. Under strong stirring 9.2×10⁻² g (4.2×10⁻⁴ mol) bBCB-ol was added andthe system stirred for 5 min. Then 3.7 mL (4.3×10⁻² mol) IB was addedfollowed by the addition of 1.1 mL (1.0×10⁻² mol) TiCl₄. Thepolymerization was allowed to proceed 60 min and terminated with 2.4 mL(1.5×10⁻² mol) distilled and prechilled allyltrimethylsilane (ATMS).After 30 min of stirring ˜5 mL methanol was added to terminate thepolymerization and decompose the TiCl₄. The reactor was removed from thecooling bath and allowed to warm to room temperature. The solution wasconcentrated by rotary evaporation, precipitated into ˜100 mL methanol,the methanol was decanted, the polymer dissolved in hexane, and washedwith 5% aqueous sodium bicarbonate and water. The organic phase wasdried over night over magnesium sulfate, and filtered through finesintered glass. Finally, the solvent was evaporated by rotaryevaporation and the allyl telechelic PIB, a colorless viscous mass, wasdried in high vacuum.

The allyl telechelic PIB was characterized by ¹H NMR spectroscopy andGPC (FIGS. 8 and 9, respectively). ¹H NMR (CDCl₃): δ=1.03-1.22 ppm (br,6H, a), 1.35-1.46 ppm (br, 2H, b), 5.6-6.0 ppm (br, H, c), 4.75-5.20 ppm(br, 2H,d); Mn,_(1H NMR)=15,034 g/mol. Mn,_(1H NMR) was calculated fromthe integrals of backbone methyl protons (—C(CH₃)₂—, δ 1.03-1.22)relative to the methylene protons or methine proton of the allyl group(═CH—, δ 4.80-5.15, and ═CH₂, δ 5.70-6.00). (See, FIG. 8). According toGPC, Mn,_(GPC)=17,127 g/mol (polystyrene standards) and Mw/Mn=1.47 (See,FIG. 9).

Example 6 Preparation of a Star Molecule with Three Allyl-Terminated PIBArms (Ø-(PIB-Allyl)₃)

The synthesis of Ø-(PIB-Allyl)₃ following the procedure described byLech Wilczek and Joseph P. Kennedy in The Journal of Polymer Science:Part A: Polymer Chemistry, 25, pp. 3255 through 3265 (1987), thedisclosure of which is incorporated by reference herein in its entirety,with the substitution of a trifunctional initiator according to thepresent invention and as described above. The first step involves thepolymerization of isobutylene to a trifunctional initiator/TiCl₄ systemunder a blanket of N₂ in a dry-box. Next, in a 500 mL three-neck roundbottom glass flask, equipped with an overhead stirrer, the following areadded: a mixed solvent (n-hexane/methyl chloride, 60/40 v/v),2,6-di-t-butyl pyridine (0.007 M), 1,3,5-tri(2-methoxyisopropyl)benzene(0.044M), and isobutylene (2 M) at a temperature of −76° C.Polymerization is induced by the rapid addition of TiCl₄ (0.15 M) to thestirred charge. After 10 minutes of stirring the reaction is terminatedby the addition of a 3 fold molar excess of allyltrimethylsilane(AllylSiMe₃) relative to the tert-chlorine end groups of the Ø-(PIB-Cl)₃that formed. After 60 minutes of further stirring at −76° C., the systemis deactivated by introducing a few milliliters of aqueous NaHCO₃, andthe (allyl-terminated polyisobutylene) product is isolated.

Example 7 Preparation of Ø-(PIB—CH₂—CH₂—CH₂—Br)₃ Anti-MarkovnikovAddition of HBr to Ø-(PIB-Allyl)₃

A 100 mL three-neck flask is charged with heptane (50 mL) and theallyl-telechelic polyisobutylene (10 grams) formed in Example 6, aboveand containing the residue of a trifunctional initiator according to thepresent invention and as described above. Air is then bubbled throughthe solution for 30 minutes at 100° C. to activate the allylic endgroups. Then the solution is cooled to approximately −10° C. and HBr gasis bubbled through the system for 10 minutes.

Dry HBr is generated by the reaction of aqueous (47%) hydrogen bromideand sulfuric acid (95 to 98%). After neutralizing the solution withaqueous NaHCO₃ (10%), the product is washed 3 times with water. Finallythe solution is dried over magnesium sulfate for at least 12 hours(i.e., overnight) and filtered. The solvent is then removed via a rotaryevaporator to produce the Ø-(PIB—CH₂—CH₂—CH₂—Br)₃ polymer containing theresidue of a trifunctional initiator according to the present inventionand as described above.

Example 8 Preparation of Ø-(PIB—CH₂—CH₂—CH₂—OH)₃ fromØ(PIB—CH₂—CH₂—CH₂—Br)₃

The conversion of the terminal bromine product to a terminal primaryhydroxyl group is performed by nucleophilic substitution on the bromine.A round bottom flask equipped with a stirrer is charged with a solutionof Ø-(PIB—CH₂—CH₂—CH₂—Br)₃ in THF. Then an aqueous solution of NaOH isadded, and the charge is stirred for 2 hours at room temperature.Optionally, a phase transfer catalyst such as tetraethyl ammoniumbromide can be added to speed up the reaction. The product is thenwashed 3 times with water, dried over magnesium sulfate overnight andfiltered. Finally the solvent is removed via the use of a rotaryevaporator. The product, a primary alcohol-terminated PIB product, is aclear viscous liquid.

Example 9 Synthesis of the Polyurethane

The allyl di-telechelic PIB of Example 5 containing the residue of thebBCB-ol initiator is first dissolved in heptane. Air is then bubbledthrough the solution for 30 minutes at 100° C. to activate the allylicend groups. The solution is then cooled to approximately −10° C. and HBrgas is bubbled through the system for 10 minutes to produce thecorresponding Br-di-telechelic PIB. After neutralizing the solution withaqueous NaHCO₃ (10%), the product is washed 3 times with water. Finallythe solution is dried over magnesium sulfate for at least 12 hours(i.e., overnight) and filtered. The solvent is then removed via a rotaryevaporator. The Br-PIB-Br product is a clear viscous liquid.

The conversion of the terminal bromine group to a terminal primaryhydroxyl group is performed by nucleophilic substitution on the bromineas follows. The Br-PIB-Br product is first dissolved in THF. Then, anaqueous solution of NaOH is added, and the charge is stirred for 2 hoursat room temperature. Optionally, a phase transfer catalyst such astetraethyl ammonium bromide can be added to speed up the reaction. Theproduct is then washed 3 times with water, dried over magnesium sulfateovernight and filtered. Finally the solvent is removed via the use of arotary evaporator. The product, a primary alcohol-terminated PIB productcontains the residue of the bBCB-ol initiator.

The HO-PIB-OH above is next dissolved in dry toluene and freshlydistilled MDI and tin dioctoate catalyst are added under a dry nitrogenatmosphere. The charge is then heated for 8 hours at 70° C., cooled toroom temperature, and poured in a rectangular (5 cm×5 cm) Teflon mold.The system is air dried overnight and finally dried in a drying oven at70° C. for 24 hours to produce a PIB polyurethane containing the residueof the bBCB-dinitiator.

Example 10 Synthesis of the Amine telechelic PIB

30 grams of allyl di-telechelic PIB polymer (Allyl-PIB-Allyl) iscombined with 150 mL of heptane and refluxed at 110° C. for about 30minutes, followed by passing HBr gas over the polymer solutions for 5minutes at 0° C. to convert the the Allyl-PIB-Allyl polymer to thecorresponding telechelic primary bromide polymer(Br—(CH₂)₃—PIB—(CH₂)₃—Br)

Next, the Br—(CH₂)₃—PIB—(CH₂)₃—Br is converted by using: (1) potassiumphthalimide; and (2) hydrazine hydrate to yield the target ditelechelicamine, NH₂—(CH₂)₃—PIB—(CH₂)₃—NH₂ by the following process. 16 grams ofbromo-ditelechelic polyisobutylene (0.003 mol) is dissolved in 320 mLdry THF. Then, 160 mL of N-methyl-2-pyrrolidone (NMP) and phthalimidepotassium (2.2 grams, 0.012 moles) are added to this solution. Next, thesolution is heated to reflux at 80° C. for 8 hours. The product is thendissolved in 100 mL of hexane, extracted 3 times with water, and driedover magnesium sulfate. Then, the phthalimide-telechelic polyisobutylene(14 grams, 0.0025 moles) is dissolved in 280 mL of heptane, then 280 mLof ethanol and hydrazine hydrate (3.2 grams, 0.1 moles) are addedthereto, and the solution is heated to reflux at 110° C. for 6 hours.The product is dissolved in hexane, extracted 3 times with water, driedover magnesium sulfate, and the hexane is removed by a rotary evaporator(rotavap) to provide the allyl di-telechelic PIB polymer.

Example 11 Synthesis of the Polyurea

To H₂N—PIB—NH₂ (1.5 grams, M_(n)=5,500 g/mol, amine equivalent 0.00054moles) dissolved in dry toluene (10 mL) is added freshly distilled MDI(0.125 grams, 0.0005 moles), with stirring, under a dry nitrogenatmosphere. Within a minute the solution becomes viscous. It is thendiluted with 5 mL of toluene and poured in a rectangular (5 cm×5 cm)Teflon mold. The system is air dried overnight and finally dried in adrying oven at 70° C. for 24 hours. The polyurea product is a paleyellow supple rubbery sheet, soluble in THF.

Example 12 Synthesis of Polyisobutylene-Polystyrene Block Copolymer

Into a 300 mL round bottom flask equipped with a magnetic stirrer isplaced 30 mL dried and distilled hexane, 20 mL dried and distilleddichloromethane and DtBP (5.0×10⁻⁵ mol) proton trap and cooled to −80°C. Under strong stirring 7.7×10⁻² g (3.0×10⁻⁴ mol) bBdClCB is added andthe system stirred for 5 min. Then 4.6 mL (5.3×10⁻² mol) IB is addedfollowed by the addition of 0.7 mL (6.0×10⁻³ mol) TiCl₄. Thepolymerization is allowed to proceed for about 60 min and then 1.8 mL(1.6×10⁻² mol) styrene is added. After 1 hour polymerization isterminated with ˜5 mL methanol. The reactor is removed from the coolingbath and allowed to warm to room temperature. The solution isconcentrated by rotary evaporation, precipitated into ˜100 mL methanol,the methanol is decanted, the polymer dissolved in hexane, and is washedwith 5% aqueous sodium bicarbonate and water. The organic phase is driedover night over magnesium sulfate, and filtered through fine sinteredglass. Finally, the solvent is evaporated by rotary evaporation and theproduct is dried in high vacuum.

In light of the foregoing, it should be appreciated that the presentinvention significantly advances the art by providing a novel, low costLC⁺P initiator that is structurally and functionally improved in anumber of ways. While particular embodiments of the invention have beendisclosed in detail herein, it should be appreciated that the inventionis not limited thereto or thereby inasmuch as variations on theinvention herein will be readily appreciated by those of ordinary skillin the art. The scope of the invention shall be appreciated from theclaims that follow.

What is claimed is:
 1. An initiator molecule defined by one of thefollowing formulas:

wherein x is Cl, or OCH₃.
 2. The initiator molecule as claimed in claim1, wherein said initiator molecule is a bifunctional or trifunctionalinitiator.
 3. The initiator molecule as claimed in claim 2, wherein saidinitiator molecule is a bifunctional initiator having the formula:

or wherein x is Cl, or OCH₃.
 4. The initiator molecule as claimed inclaim 2, wherein said initiator molecule is a trifunctional initiatorhaving the formula:

wherein x is Cl, or OCH₃.
 5. The initiator molecule as claimed in claim1, wherein said initiator molecule is defined by the chemical formula4,9-dichloro-2,4,7,9-tetramethyl-tricyclo[6.2.0.0^(3,6)]deca-1(8),2,6-triene.